I have a 2007 raptor 700r se. It was fuel injected, it has a hmf exhaust and k&n airfilter. When I ride it, it'll spit and sputter, you can't get the rpm's high even if you hold the throttle all the way down, it also has problems starting up. I have been told that it needs a fuel optimizer, but I don't want to spend that much money on one and it need be it. Help please????

 

Well the only solution would be to get a fuel programmer or put the stock pipe back on. Right now you are running way too lean with a full pipe and less restrictive filter. These big bores already run lean from the factory so adding a pipe and filter without changing the fuel mapping accordingly makes it a lot worse. Look on ebay for a used dobeck style programmer if you don't have the money for a PCV.

 

What if I keep the hmf on it and put a stock air filter back on it?

 

It may help a little bit but like I said, the big bores already run lean from the factory so it will still bog and stall out

 

Did you re-jet the bike it would help alot if your running all these things on it and you might have to get a fuel optimizer or just take the pipe off and put the stock pipe on because like the other guy said your running way to lean for the bike to run right